Hydraulic valve



Aug. 4, 1942. A. E. BAAK HYDRAULIC VALVE Filed March 11, `1939 Patented Aug. 4, 1942 HYDRAULIC VALVE Albert E. Baak, Minneapolis, Minn., assignor Minneapolis-Honeywell Regulator Company, Minneapolis, Minn., a corporation o! Delaware Application March ill, 193.9, Serial No. 261,229

(Cl. MP3- 41) My invention relates to improvements in hydraulic transmission mechanisms, particularly when used as means for actuating valves and the like.

The principal object of my invention is to provide a hydraulic transmission mechanism for actuating a valve or the like wherein positive acting release means are provided for insuring return movement or retraction of the valve or similar device after it has been moved under the influence of pressure of hydraulic medium. The attainment of this object is particularly advantageous in valve actuators controlling gas valves and the like where there must be assurance that the valve is Aclosed automatically in response to control equipment. in the past electric valves have been common ,y used. These valves being ci the solenoid type, have a serious and aggran vating tendency to stick in the open position creating a hazardous condition.

Another object of my invention is the provision ci a pressure operated device having a positive, mechanically actuated pressure release means for releasing pressure to actuate the device.

Another object of my invention is the provision of a hydraulically operated valve device employ- -ing an electrically driven iiuid forcing means comprising an armature mounted on a shaft arranged to simultaneously actuate a pressure release valve when the motor is energized. Figure l is a sectional view of a preferred ernbodiment of my invention, and

Figure 2 is a cross sectional detail view taken along the line 2 2 of Figure l.

l Referring to Figure l of the drawing, numeral i@ designates the body of a valve which in the present instance is a diaphragm type gas valve. The inlet of the valve is at H and the outlet at l2, the valve body being internally conlgurated so as to form a seat i3. The upperpart of the valve body is o i circular conformation having a flange N. Numeral i5 designates a cover for the valve having a flange IE corresponding to the flange I4. Flanges t4 and I6 are securely fastened together by screws I1, the peripheral portions of a flexible diaphragm I8 being interposed between the flanges in sealing relation therewith. Adjacent the central portion of the diaphragm I8 is a iiexible valve seat disc i9 and on the opposite side of the diaphragm is a metal backing disc 29. A washer 2l is disposed on that side of the valve disc i9 away from the diaphragm, and the discs and diaphragm are secured together by means of a bolt 22.- The diaphragm I8 and seat disc I9 may be made of a suitable flexible material such as leather. The seat disc i9 is adapted to seat upon the seat i3 and to thereby prevent flow of fluid through the valve. The structure so far described comprises a diaphragm type gas valve of conventional construction.

Numeral 25 designates a three-way pilot valve which may be oi generally cylindrical shape having flanges 2t and 2l at its opposite ends. 'The lower iiange 2l is secured to the cover l5 of the diaphragm valve by means of screws 28 and 2t, there being a gasket Stof suitable sealing material interposed between the iiange 2l and the cover l5. There is anopening 3l in the cover |15 of the diaphragm valve coaxial with an openlng 32 in the gasket il@ and with a channel 33 in the body of the three-Way valve 25.

The upper part of the body of the three-way valve 525 has an opening or bore 34 and a smaller bore 35 the lower part of which forms a valve seat 36. The bore is screw threaded and screwed into this bore is' a hanged nut 3l. The lower part of the nut 3l forms a valve seat 38 similar to the valve seat 35 and the upper part of the nut 3l is recessed at 35i so as to form `an annular shoulder for purposes ci retaining a coil spring d0. Disposed between the valve seats 36 and 38 is a valve member it so formed as to seat upon the valve sect ce when moved downwardly and to seat upon the valve seat 38 when moved upwardly. A stem 32 connected to the valve member tl. The sternextends through nut 3l and at the upper end is a collar disc 43. The upper end ofthe coil spring f3@ bears against the collar disc 653 so that the valve member il is normally urged against the upper seat 38. The channel 33 in the bodyof the three-way valve communicates laterally with the space between the valve seats Bfiand 38 and a channel M in the valve body communicates with the space between the valve seats through the valve formed in paw by the seat 35.

.The flange is secured to the bottom of a casing Qt forming a liquid reservoir by means of screws B9 and bil there being a exible diaphragm 5l interposed between the ange 28 and the bottorn of the casing t3. The collar disc 43 previously described bears upwardly against the central portion of the diaphragm 5l. The space within the casing i8 is partially iilled with a hydraulic iiuid 52 which is preferably oil and this hydraulic liquid is adapted to be pumped by means of a gear pump indicated generally at 53 and mounted in a portion of the casing 48. The gear pump 53 is driven by an electric motor indicated generally at 54, the electric motor comprising a winding 55, a laminated core 58, and an armature 51.

'Ihe winding 55 is wound around a portion of the core 55 in the usual manner and the core 58 and amature 51 form a more or less complete magnetic circuit for magnetic flux induced in the core by current in the winding. The amature 51 is mounted on a shaft or spindle 58 between portions of the core 58 constructed and arranged to form poles on opposite side of the amature in the usual manner. The shaft 58 of the motor is journalled in a boss 58 formed on an inner wall of the casing 48 and is also journalled in portions of the casing 48 which form a housing for the gear pump 58. One of the gears of the gear pump designated at 88 is splined onto the shaft 58 as may be seen on both Figure 1 and Figure 2 so that the gear 88 is constrained to rotate with the shaft 58. 'Ihe gear 58 drives the other gear 8| of the gear pump (see Figure 2) which is suitably mounted on a counter shaft. The inlet to the gear pump is designated at 82 and communicates with the liquid reservoir formed within the casing 48. A channel 83 formed in a portion of the casing 48 communicates with the discharge of the gear pump and with a recessed portion 84 formed at the central portion of the bottom of the casing 48. The,l armature 51 of the motor 54 is secured to the shaft 48 so that the motor can drive the gear pump so as to pump oil from within the casing 48 through the channel 88 into the recess 84. The diaphragm is adjacent the recess 54 so that a liquid chamber is formed within the recess 84 and when hydraulic liquid, that is, the oil, is pumped into this chamber its pressure acting on the diaphragm 5| is suillcient to force the valve stem 42 downwardly against the force of coil spring 48. l

The right end of the shaft 58 extends beyond the gear pump 58 into an opening 51 in a portion of the casing 48 and this end of the shaft forms a valve head 88. 'I'he valve head 88 cooperates with a valve seat 88 formed by the opening 81 within casing 48. The opening 81 communicates with the oil reservoir by a channel 18 and with 4recess 84 by means of a channel 1|. 'I'he shaft 58 may be longitudinally reciprocated so that the valve 58 is moved against and away from the seat 88. y

Disposed on the shaft 58 adjacent to the armature 51 is a spring retaining disc 12. Encircling the shaft 58 is a coil spring 18, one endof which bears against the disc 12 and the other end of which engages in a suitable recess formed in a portion of the casing 48. The coil spring 18 continuously urges the armature 51 and shaft 58 to the left in a direction to move valve 58 awayfrom seat 88. With the parts in the positions shown the motor 54 is not energized and the force of coil spring 13 keeps the armature 51 in a position with its magnetic center displaced to the left of the normal path of magnetic ilux between the poles formed by the core 58. When the motor 54 is energized, as well as rotating the armature 51, it is moved to the light in the manner of a solenoid so thatl its magnetic center is brought to a position wherein the path of magnetic flux between the poles oi' the core 58 will be shortest. Movement of armature 51 and shaft Y 58 to the right is permitted because the driving gear 88 of the gear pump is splined onto the shaft and when the shaft 58 is moved to the right ln the manner described valve 88 seats on valve back into the reservoir within the casing 48.

Thus when the gear pump 58 is started to pump oil into the chamber formed by the recess 84 the release valve 88 is automatically closed and when the motor 54 is stopped the armature 81 and shaft 58 will move into the position shown so as to open valve 88 and quickly release the pressure from above the diaphragm 5|.

The upper part of the casing 48 is closed by means of a cover 14 secured to the casing by screws 15 and 18 there being a sealing gasket 11 interposed between the cover and the upper part of the casing 48.

The diaphragm valve which I have shown in Figure l is particularly adapted to control the flow of gas in a gas fired heating system. Nu-

,meral 18 shows diagrammatically a gas main which may beconnected to the inlet of the diaphragm valve and the outlet of the valve may be connected to a conventional gas burner by means of a conduit 18. The channel 44 in the body of the three-way valve communicates with the gas supply by means of a tube 88 and a bleed tube 8| is connected to the opening or bore 84 in the upper part of the body of the three-way valve so as to bleed gas therefrom.

The temperature of the objective being` heated such as a space in a building for example is controlled by means of a thermostat 82 which may be of conventional type comprising a bimetal element 88 arranged to actuate a switch blade 84 cooperating with an electrical contact 55. Adjacent the blade v84 is a permanent magnet 88 so arranged that the blade 84 moves against and away from the contact 85 with a snap action.

In operation of the device and the system in which it is used, whenever the temperature of the space ybeing heated falls to a predetermined value, blade 84 of the thermostat engages contact 85 completing a circuit energizing the -wlnding 55 as follows: from wire 81 to the thermostatic element 88, blade 84, contact 85. wire 88, and winding 55 back to the wire 89. The wires 81 and 88 may of course be connected to any suitable source of power. When winding 55 is energized armature 58 rotates so as to drive the gear Dump and as above described the shaft 58 is moved to the right so as to seat valve head 88 on the seat 88 closing oli communication between the channels 1| and 18. As the gear pump operates, oil is .withdrawn from within the reservoir in casing 48 and forced into the chamber above the diaphragm 5|. As the pressure above diaphragm 5| builds up, the valve' stem 42 and valve member 4| are `forced downwardly from the position shown until valve member 4| engages the seat 88. When valve member 4| engages seat 88, the supply of gas to the space above diaphragm |8 through tube 88 is cut olf and the gas above diaphragm I8 is released through the channel 88 to the bore or opening 84 within the body of valve 25 from which it is bled ofi' to an auxiliary pilot burner through the bleed tube 8|. When the pressure above diaphragm |8 is released the pressure from gas main 18 acting on seat disc |8 will break the deenergizing the motor 54, the armature 51 and shaft 58 will take the position shown in Figure 1 with valve head 68 away from seat 69. In this manner the pressure above diaphragm 5| will quickly be released, the oil from above the diaphragm passing back into the reservoir through the channels 'Il and 10. The coil spring 40 will quickly move valve member 4I into the position shown in Figure 1 and pressure from the gas main 18 will be communicated to the space above diaphragm I8 through the tube 80, channel M, channel 33, and opening 3l. -The pressure above the diaphragm I8 will snap it downwardly into closed position of the valve in the conventional manner of operation of diaphragm valves.

From the foregoing it is apparent that I have provided a novel and meritorious arrangement for controlling the actuation of valves or similar devices. While I have shown a preferred form of .my invention wherein a diaphragm gas valve is hydraulically controlled my arrangement might also be used to control other devices adapted to be hydraulically actuated. My invention is however particularly adapted to the actuation of pilot valves which control diaphragm gas valves or the like. With my arrangement the danger of the pilot valve sticking in an open position so as to keep the diaphragm valve open at a time when it should be closed, is entirely obviated. When the pilot valve of my arrangement is to move into a position to cause closure 4 lof the diaphragm valve the valve for releasing .pressure from above the diaphragm 5I is positively actuated so that there is no way that the pilot valve could fail to return it to the position y shown in Figure 1. Thusthe dangers attendant to electric valves sticking in open position or pressure operated release valves failing to operate in the intended manner are avoided, my arrangement .providing a reliable and economical construction capable of supplantmg the aforementioned devices but without -possessing their inherent disadvanatges. The gear pump and the driving motor for it may be made very small and compact but yet being able to control a relatively large diaphragm valve by means of the Ipilot valve.

, The single embodiment of my invention which I have disclosed 4in-detail is a preferred form and application-of it but there are various forms which it may take and uses 'to which it may -be put which areintended to fall within the spirit and scopev of the invention. The invention is therefore vto be limited only by the appended claims.'

` I claim as my invention:

1. Fluid pressure control means comprising in combination, a pump for supplying fluid under pressure, a valve for relieving pressure supplied by said pump, and motor means for operating said pump and said valve comprising an electrif said valve, and motor means for simultaneously rotating said shaft to operate said pump and moving said shaft longitudinally to close said valve.

3. Fluid pressure control means comprising in' combination, a rotary pump for supplying fluid 'under pressure, a shaft for rotating said pump,

a splined connection between said pump and said shaftv to permit longitudinal movement of said shaft, a valve for controlling pressure supplied by said pump.` a connection between said shaft and said valve, and motor means for'operating said pump and valve comprising an electrical winding and an armature associated with said shaft, energization of said winding causing rotation of said shaft to operate said pump and translation of said shaft to operate said valve.

4. Fluid pressure control means comprising in combination, a pump for supplying uid under pressure, a shaft for driving said pump, a connection between said shaft and said pump to permit longitudinal movement of said shaft, a valve member carried by one end of said shaft for controlling pressure supplied by said pump, and motor means for operating said pump and valve comprising an electrical winding and an armature associated with said shaft, energization of said winding causing rotation of said shaft to operate said pump and translation of said shaft to vvoperate said valve.

5. Fluid pressure control means comprising in combination, a pump for supplying fluid under pressure, a valve for relieving pressure supplied by said pump, and motor means comprising a single electrical winding and a unitary structure actuated thereby upon energization thereof for operating said pump and simultaneously closing said valve.

6. Fluid pressure control means comprising in combination, a pump for supplying iluid under pressure, a valve for controlling pressure supplied by said pump, an integral structure for operating said pump and said valve, and electrical winding means for actuating said structure upon en- 

